Ten years ago, the BlackBerry was known as a Wall Street icon or a geek organizer, far too expensive and nerdy to be used by mere mortals.

Today, “BlackBerry” is the new “Kleenex,” the generic name people give to any personal digital assistant, or PDA. Treo and other companies are giving BlackBerry a run for its money, while cute devices like the T-Mobile Sidekick have made owning a PDA-like cell phone hip. When little portable computer phones get Paris Hilton endorsements, it’s safe to say that their bigger cousin, the laptop, is going the way of the dinosaur.

“In a physical sense, there are many phones that now have QWERTY keyboards and scaled down Intel processors,” says Kurt Collins, business development manager at Photobucket, an online publisher of visual digital content. “Many PDA phones come with software that allows the user to not only check e-mail, but also read and write Microsoft Office documents.”

Cell phones and PCs now rank as the most important devices for American consumers under 40, outranking even the TV, according to a survey by Forrester Research. The way that translates into the business market is that more and more consumer technologies are being used by workers in the office and out in the field. Laptop sales are, by some estimates, on schedule to outpace PC sales. But cell phones are already surpassing land-line phones in such locations as Europe and certain states, such as North Dakota, according to regulators. In mid-2006, the number of cellular connections in the world reached 2.5 billion, having just climbed over the 2 billion mark a year ago, according to estimates from Wireless Intelligence, a research venture that tracks the global market for mobile technology.

The sharp trajectory of growth for cell phones and the growing number of PC-like features being incorporated into their design are fueling the theory that the cell phone is becoming the new laptop. Here are the reasons why:

• It can e-mail. The most mundane cell phone — the kind that comes free with a phone plan — has e-mail as a standard feature. It is usually carrying AOL and Yahoo!, but MSN’s Hotmail can be accessed indirectly. The low-budget phones require multiple number pad strokes to type individual letters, but several reasonably-priced phones have QWERTY keyboards, the standard computer keyboard. Some brands offer nearly full-sized keyboard attachments that connect to the phone.
• It can Web-browse. Every major cell service offers Web browsing for a few extra dollars a month. Many sites, such as Google and MSN, format their pages for easy cell phone reading. Cell phone companies also aggregate content, making it easy to get the latest world, business or entertainment news on the phone.
• It is small. Traveling with electronics is cumbersome, especially for those who are on-the-go all the time. At airports, laptops must be taken out of their bags, placed on the security conveyor belt and gathered up on the other side of the gate. A cell phone simply needs to be turned off at takeoff.
• It has Windows. Windows Mobile has now come into its own on portable devices. It’s getting to the point where all software — Word, Excel, perhaps even PowerPoint — will be on your cell phone.
• It has Bluetooth capabilities. Also becoming a standard, Bluetooth allows your cell phone to communicate with other phones and computers in a fast, efficient way. Files can be transferred quickly between your computer and your cell, turning your phone into a virtual memory stick.
• It is cheaper (for now). The biggest threat to the bulky laptop is price. A top-of-the-line, fancy cell phone will cost you about $600, or one-fourth the cost of a top-of-the-line, fancy laptop. Until the mythological $100 notebook is commonplace, cell phones are the cheaper and more efficient road to take.